Eating for Longevity
Is there such a thing as a longevity diet? Increasingly, studies suggest the answer is yes.
Around the world, certain groups of people enjoy exceptionally long lives. Consider the lucky people of Okinawa. These Pacific Islanders have an average life expectancy of more than 81 years, compared to 78 in the United States and a worldwide average of just 67. Closer to home, members of the Seventh Day Adventists, who typically eat vegetarian diets, outlive their neighbors by four to seven years on average.
The residents of the San Blas islands off the coast of Panama very rarely suffer from high blood pressure and heart disease. Indeed, research shows that their rate of heart disease is only nine per 100,000 people, compared to 83 per 100,000 among nearby Panamanians on the mainland.
What makes these groups so fortunate? A growing body of evidence suggests that diet is one of the important contributors to longevity and healthy living. Here’s what’s on the menu of people who enjoy long and healthy lives.
Foods for a Healthy Heart
Most of us know to go easy on saturated fat, the kind found in meat and high-fat dairy products. Saturated fats have been shown to raise blood cholesterol levels into the danger zone. Just as important is what you should be eating. For heart health and longevity, you should eat:
Plenty of fruits and vegetables: Packed with fiber and nutrients, fruits and vegetables are also relatively low in calories. Studies consistently show that diets plentiful in fruits and vegetables help people maintain a healthy weight and protect against cardiovascular disease.
Whole grains: Like fruits and vegetables, whole grains pack a lot of nutrition into a low-calorie package. Grains like oats and barley are also rich in a long list of disease-fighting compounds.
In 2009, researchers at the University of Texas Health Sciences Center in Houston reported that study participants whose diets included plenty of whole grains and fruit cut their heart disease risk by almost half compared to those whose diets favored meat and fatty foods. Findings from more than 161,000 nurses enrolled in the Nurses’ Health Study also show that whole grains protect against type 2 diabetes, a disease that increases the danger of heart disease.
Nuts: For too long, nuts were banished from the list of healthy foods because they’re high in fat. They are. But the fat they contain is mostly unsaturated, which protects against heart disease.
Dark chocolate: Researchers now think that high blood pressure and heart disease are exceedingly rare among residents of the San Blas islands because they eat chocolate, and lots of it. Components in dark chocolate called polyphenols are believed to lower blood pressure and improve the flexibility of blood vessels. In a 2008 study, researchers at the University of Aquila gave volunteers with hypertension 100 grams of dark chocolate daily. After 15 days, their blood pressure readings were significantly lower and their insulin sensitivity had improved.
Foods for a Vital Brain
The basic advice is simple: What’s good for your heart and blood vessels is also good for your brain. That means eating a diet centered on fruits and vegetables with plenty of unsaturated oils, such as olive oil, and plenty of whole grains. Foods that may add extra protection include:
Blueberries and other antioxidant-rich fruits: Ongoing research at the Jean Mayer Human Nutrition Research Center on Aging at Tufts University suggests that foods especially high in antioxidants, including blueberries, grape juice, and walnuts, protect against age-related changes in the brain that lead to memory loss and even dementia.
Fish: High in omega-3 fats, fish and shellfish have been shown to protect against irregular heart rhythms than can lead to heart failure. New evidence suggests that in addition to heart protection, the fatty acids, such as DHA and EPA, found in fish oil (and ALA found in flaxseed) may offer a defense against depression and age-related memory loss.
Low-salt foods: Researchers have known for years that less salt in the diet means lower blood pressure. Now new evidence suggests that keeping blood pressure down may also protect brain cells and decrease the risk of age-related memory loss and even dementia.
“High blood pressure can damage the vasculature that supplies the brain with oxygen and nutrients,” explains Tufts University neuroscientist Aron Troen, PhD. That may explain why people with chronic hypertension seem to be at higher risk of developing age-related cognitive impairments.
Coffee: A growing number of studies suggest that coffee has several surprising health benefits. In addition to potentially lowering the risk of type 2 diabetes, drinking coffee may reduce the risk of age-related mental decline.
The latest evidence comes from a Finish study of 1,409 volunteers published in the Journal of Alzheimers Disease in 2009. It found that people who regularly drank coffee during their middle-aged years were significantly less likely to suffer dementia and Alzheimer’s later in life. Those who drank three to five cups daily had a 65% reduction in risk.
Foods for Strong Bones
Bone loss and osteoporosis are among the leading reasons for disability in later life. And once seniors become disabled, their health often declines in many other ways. Although some bone loss with age is inevitable, eating foods rich in calcium and vitamin D can slow the process and prevent disabling fractures. Among the top choices:
Low-fat dairy products: “The body needs vitamin D in order to absorb calcium,” says Robert P Heaney, MD, a leading expert on osteoporosis. “But adequate levels of protein are also necessary to keep bones strong.” For that reason, he argues, dairy products like milk and yogurt are the best sources of calcium because they contain the full array of nutrients needed for healthy bones.
Dark green leafy vegetables: Collard greens, spinach, and broccoli are good sources of calcium.
Tofu: Look for brands made with calcium sulfate, which contain the highest levels of calcium. A half-cup contains about 250 milligrams of calcium. (Adult women should consume about 1500 milligrams a day, according to Heaney.)
Unfortunately, getting enough vitamin D turns out to be trickier than getting enough calcium. Although many foods are fortified with vitamin D, diet alone isn’t able to provide enough. Our skin converts sunlight to vitamin D; but with age, that process becomes less efficient. (During the winter months in most parts of the United States, the sun is too weak to generate vitamin D production.)
While experts continue to debate the optimal levels of vitamin D, Heaney recommends taking 1,000 to 2,000 international units (IU) a day in supplement form. Boosting vitamin D is particularly important as you get older, he points out, since the skin becomes less efficient at generating this crucial nutrient from sunlight.
Beyond Nutrients: The Joy of Eating
A diet abundant in nutrients is obviously important to longevity. So is enjoying what you eat-- and especially finding joy in sitting down to meals with family and friends.
Studies of centenarians the world over suggest that social connections and finding meaning in life are both crucial to longevity. The long-lived people of Okinawa say one reason they enjoy long and healthy lives is something they call ikigai, or “finding your reason to live.”
By Peter Jaret, WebMD Feature; Reviewed by Louise Chang, MD